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Subsecond Spikes in Fermi GBM X-Ray Flux as a Probe for Solar Flare Particle Acceleration
Trevor Knuth1, Lindsay Glesener1
1The School of Physics and Astronomy, University of Minnesota, USA.
The Astrophysical Journal
|January 24, 2022
Summary
Researchers analyzed fast X-ray fluctuations from solar flares using Fermi Gamma-ray Burst Monitor (Fermi GBM) data. They identified subsecond spikes, providing insights into electron acceleration mechanisms during solar events.
Area of Science:
- * Solar Physics
- * Astrophysics
- * Plasma Physics
Background:
- * Solar flares accelerate electrons, releasing significant energy.
- * Studying rapid X-ray flux fluctuations (≤2s) probes electron acceleration mechanisms.
- * Temporal analysis of X-ray spikes tests the validity of different acceleration models.
Purpose of the Study:
- * Analyze fast fluctuations in nonthermal X-ray flux from solar flares.
- * Investigate subsecond X-ray spikes using Fermi Gamma-ray Burst Monitor (Fermi GBM) data.
- * Develop a rigorous method for identifying and measuring temporal properties of these spikes.
Main Methods:
- * Analyzed Fermi GBM data from two M9.3 solar flares (SOL2011-07-30, SOL2011-08-04).
- * Identified, counted, and measured temporal properties of subsecond X-ray spikes.
- * Compared spike characteristics (duration, timing, periodicity) with acceleration mechanism timescales.
Main Results:
- * Identified X-ray spikes primarily in 60-100 s spans during the impulsive phase.
- * Average spike durations were 0.49 s and 0.38 s for the two flares.
- * Spike duration distribution followed a power law (-1.2 ± 0.3 index) for one flare; one interval showed 1.7 Hz periodicity.
Conclusions:
- * Fermi GBM data are effective for examining subsecond X-ray spikes.
- * The study presents a robust method for analyzing these temporal features.
- * Findings offer constraints on electron acceleration mechanisms in solar flares.
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